Historic flood forced to overflow 2,000 m3/s
Starting from the night of November 16, heavy rain appeared in the Don Duong Lake basin, water from upstream flooded into the lake with a peak flood flow of 1,096 m3/s. At 9:00 a.m. on November 17, the lake's water level was 1041.778 m, with a overflow flow of 200 m3/s.
Ho Don Duong has gradually increased the regulated discharge level of 300-400-500 m3/s from 9:00 a.m. to 11:00 a.m. on November 17 and reached the largest discharge flow of 600 m3/s from 11:15 a.m. to 1:30 p.m. on the same day. After that, the discharge will gradually decrease to 250 m3/s when the rain in the reservoir basin decreases.
However, at 12:00 on November 19, when the lake's water level reached the elevation of 1,040.090m, heavy rain appeared again in the Don Duong reservoir basin and the rain became stronger.
At 00:00 on November 20, the average rainfall measured at 186.5 mm caused a historical flood peak of 2,090 m3/s ( recent lake water level was 1,043.138 m, overflow flow was 2,000 m3/s) and the total flood volume to the lake reached 149.8 million m3.
Mr. Do Minh Loc, Deputy General Director of Da Nhim - Ham Thuan - Da Mi Hydropower Joint Stock Company, said that at the time when the water level of Don Duong Lake reached its historic flood peak, the company reported to departments and branches of Lam Dong province for guidance.
Following the direction of the Lam Dong Provincial Civil Defense Command, the Company used the 1,043.2 m increase in water level to extend the preparation time and complete the evacuation of people in the downstream area before starting to release large regulators.
The flow of discharge through the spillway reached a maximum of 2,000 m3/s at 00:00 on November 20, then gradually decreased corresponding to the amount of water flowing into the lake. By 3:00 a.m. on November 22, the overflow flow had decreased to 300 m3/s, the lake's water level was at 1,040.910 m and continued to decrease.
Comply with instructions and ensure regulations
In more than 60 years, this is the biggest flood since Don Duong Lake was put into operation in 1964 to date. From 0:00 on November 16 to 00:00 on November 21, the total rainfall in the Don Duong Lake basin was 448.5 mm, the total floodwater in the lake reached 221.0 million m3, equivalent to 142.5% of the reservoir capacity.
During the flood regulation operation, the company complied with the correct procedures. At the same time, closely coordinate and strictly implement the direction of the Lam Dong Provincial Civil Defense Command.
"Before releasing major regulators, the company promptly notifies local authorities and people in the downstream area to organize the relocation and evacuation of people and property from the danger zone" - Mr. Do Minh Loc, Deputy General Director of Da Nhim - Ham Thuan - Da Mi Hydropower Joint Stock Company added.
During the discharge process, the company regularly implements the "4 on-site" motto; organizes regular and continuous monitoring, inspection and supervision of dams during the flood cut-off period; contacts and reports to the Lam Dong Provincial Civil Defense Command and communes along the downstream area of Don Duong Lake.
Currently, the items of earth dams, spillways, and Don Duong Lake are operating normally, safely, reliably, and stably in all operating conditions, ensuring absolute safety for the downstream area.
Weather forecast is still complicated, the Company will continue to strictly implement the "4 on-site" motto, closely monitoring the meteorological - hydrological situation. At the same time, coordinate with authorities and operate the reservoir according to the correct procedures to ensure absolute safety for the project and people in the downstream area.
Millions of arms turn to compatriots affected by storms and floods
Consecutive storms and floods caused by storms have caused many deaths, missing people, and injuries; many houses and production and business establishments have had their roofs blown off and suffered heavy damage. People across the Central and Northern mountainous provinces are struggling day and night to cope with floods and heavy losses in human lives and property that cannot be mentioned...
"A piece of food when hungry is worth a package when full", with the spirit of mutual love that has always been a beautiful image of the Vietnamese people, the Golden Heart Social Charity Fund calls on domestic and foreign philanthropists to join hands to share with people affected by floods to have food, clothing, shelter, students have books to go to school...
The Golden Heart Social Charity Fund would like to sincerely thank the precious feelings of agencies, businesses, and domestic and foreign philanthropists.
Please send any help to: Golden Heart Social Society Fund, No. 51 Hang Bo, Hoan Kiem, Hanoi. Phone: 024.39232756. Account number (STK): 113000000758 at Vietinbank Hoan Kiem Branch, Hanoi. STK: 0021000303088 - at Vietcombank - Hanoi Branch, STK: 12410001122556 - at BIDV - Hoan Kiem Branch. Or scan the following QR code:
